Final answer:
Psychoactive substances, including cigarettes, marijuana, and alcohol, affect cognitive functions and emotional responses, leading to altered states of consciousness and potentially addiction. They impair reaction time, reduce alertness, and can change behavior, with long-term use leading to serious health risks and social consequences.
Step-by-step explanation:
Psychoactive substances such as cigarettes, marijuana, alcohol, and other drugs can significantly impair our ability to think clearly and can affect our emotional responses to trigger situations. Substances like alcohol can create feelings of euphoria at low doses but lead to sedation and decreased reaction times as the dose increases.
Alcohol and certain prescription medications are categorized as central nervous system depressants, which affect neurotransmitter systems like GABA, leading to lowered levels of alertness and reduced behavioral control.
This can culminate in memory loss and potentially cause long-term effects such as fetal alcohol spectrum disorder (FASD) when consumed by pregnant individuals.
On the other hand, drugs like marijuana can alter mood and consciousness, while stimulants such as cocaine and amphetamines elevate dopamine neurotransmission, enhancing mood and energy levels but also potentially leading to addiction.
Continuous exposure to stress, which may also be exacerbated by substance use, can have negative consequences like increased risk of heart disease or impaired immune system function.